Journal of the Iranian Chemical Society最新文献

This study aimed to enhance the permeability and antifouling properties of the polymer membrane of polyethersulfone (PES) through the modification with TiO₂–AgBr–Ag–SBA-15. The hydrothermal process is used to create silica nanoparticles (SBA-15), which involved the use of tetraethylorthosilicate as a precursor and a copolymer Pluronic P123 (as a mold and the structure maintainer after solvent exiting). Then, SBA-15 nanoparticles are added to the preparation solution of TiO₂–AgBr–Ag, resulting doping nanoparticles (TiO₂–AgBr–Ag–SBA-15) were incorporated into the casting solution to achieve weight percentages of 0.4, 0.6, 0.8 and 1 in the final membranes. The nanoparticles were characterized using FESEM, FT-IR, XRD, XPS and EDX. Meanwhile, the membrane properties were studied using FESEM, FT-IR, CA, AFM and membrane performance tests. The hybrid membranes exhibited a less hydrophobic surface, which consequently resulted in water permeability. Moreover, the antifouling properties were notably improved, resulting in a considerable improvement in permeability without compromising the membrane's ability to remove unwanted substances. At 3.5 bar pressure, the pure water flux of the 0.8 wt% PES/TiO₂–AgBr–Ag–SBA-15 membrane was two times higher than that of the pristine membrane. Flux recovery rate of 1 wt% PES/TiO₂–AgBr–Ag–SBA-15 membrane can reach 90%, and the antifouling performance is excellent.

This work presents a comprehensive study of the UV–Visible and fluorescence properties, as well as the redox behavior of the [Au^III(Salen)]Cl complex in acetonitrile. The [Au^III(Salen)]⁺ complex exhibited intriguing fluorescence and phosphorescence characteristics on an indium tin oxide (ITO)-coated glass plate when excited at wavelength λ_exc ~ 260 nm, with fluorescence emission observed at λ_ems ~ 437 nm and phosphorescence at λ_ems ~ 520 nm. The origin of fluorescence emission was attributed to the intra-ligand charge transfer effect, commonly known as the "Push–Pull" effect. The electrochemical behavior of [Au^III(Salen)]⁺ on a glassy carbon electrode (GCE) revealed a remarkable one-step three-electron reduction process, leading to the reduction of [Au^III(Salen)]⁺ to Au(0). Furthermore, the reduction of [Au^I(Salen)]⁻ to Au(0) resulted in the removal of gold metal from the SalenH2 ligand. The electrochemical results suggested a mixed diffusion-adsorption redox process occurring at the GCE surface, indicating the involvement of both diffusion and adsorption during redox reactions. The cyclic voltammogram demonstrated the non-reversibility of the electrochemical redox reactions. Overall, the redox behavior of the [Au^III(Salen)]Cl complex proved to be intriguing, opening up avenues for further exploration and potential applications of this complex in various fields.

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This study involves the preparation of sodium alginate poly grafted (fumaric acid-polyacrylic acid)/graphene oxide, SA-g-p(FA-AA)/GO hydrogel to explore its potential as a promising adsorbent for water treatment mainly chromium (VI) and lead (II) removal. Prepared adsorbent was characterized by FTIR, TGA, XRD, FESEM, and TEM techniques for exploring the chemical structure, thermal stability, crystallography, surface area and morphology, as well as pore size and distribution of SA-g-p(FA-AA)/GO, respectively. The average size of the prepared nanoparticles was observed to be 78.48 nm. The TEM images exhibit a predominantly spherical shape and heterogeneous. Effect of different physiochemical parameters such as pH, temperature, adsorbent dosage, and contact time was explored for maximum metal adsorption. The results of the study revealed that the maximum adsorption capacity of SA-g-p(FA-AA)/GO (0.045 mg g⁻¹ for Cr (VI) and 22.371 mg g⁻¹ for Pb (II)) was achieved under optimized conditions, i.e., adsorbent dose of 0.05 g at 25 °C for pH of 2, 4.5 when contact time of 5 and 100 min was used for Cr(VI) and Pb(II), respectively. Data fits best to the pseudo-second-order kinetic equation revealing the multilayer adsorption of Cr (VI) and Pb (II) ions on the heterogeneous adsorbent surface. Thermodynamically, the process of Cr (VI) and Pb (II) adsorption was non-spontaneous, exothermic and feasible revealing the potential of the prepared adsorbent to be used as an efficient adsorbent for metal removal.

The catalytic efficacy of ruthenium (Ru)-exchanged montmorillonite, a well-established heterogeneous catalyst, was systematically explored to synthesize diverse bis(indolyl)methanes. The developed methodology consistently yielded the desired products with satisfactory to excellent yields, while notable advantages of the proposed approach encompassed minimal reaction times and solvent-free conditions. Furthermore, the method was characterized by its procedural simplicity, facile catalyst synthesis, ready accessibility of the starting materials from commercial sources, and the potential for catalyst recyclability.

In this research, a Fe₃O₄/Al₂O₃/CuO magnetic nanocomposite (NC) was prepared by co-precipitation method for photocatalytic activity and identified using VSM, TEM, FE-SEM, EDX, XRD and DRS techniques. Based on the TEM analysis, the structure of NC was observed as nanorods. Also, the presence of CuO was confirmed by EDX and XRD analyses. Using the DRS spectrum results, the energy band gap of Fe₃O₄/Al₂O₃/CuO NC was determined as ~ 2 eV. The synthesized compound was used as a photocatalyst for the degradation of methylene blue under sunlight irradiation. The reaction process was investigated by ultraviolet–visible spectroscopy. According to the obtained results from MB degradation about 95 percent of MB (10 mg/L) was decomposed after 25 min under sunlight irradiation. Furthermore, even after five cycles, the rate of MB degradation could still exceed 90 percent. Also, based on the obtained results, the synthesized NC can be recovered and reused in the photochemistry process. Additionally, based on the results, the Fe₃O₄/Al₂O₃/CuO NCs show high performance photocatalytic activity toward the degradation of MB under solar radiation.

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In the present study, the integration of magnetic dispersive micro-solid-phase extraction (MD-µSPE) with hollow fiber liquid-phase microextraction (HF-LPME) prior to gas chromatography–mass spectrometry (GC/MS) was developed to preconcentrate and determine trace amounts of chlorpyrifos pesticide. Azolla filiculoides fern biomass was loaded by magnetite nanoparticles to prepare magnetic adsorbent (azolla@Fe₃O₄). The structural characteristics of the produced magnetic nanocomposites (MNCs) were investigated by FESEM, TEM, VSM, FTIR, EDX, and XRD methods. In the proposed MD-µSPE/HF-LPME method, the adsorption/desorption variables in MD-µSPE step were optimized by Taguchi fractional factorial design. After chlorpyrifos adsorption in the optimized condition of MD-µSPE (V_sample = 50 mL, contact time = 15 min, solution pH = 3, adsorbent mass = 0.05 g, ionic strength = 0.01 mol L⁻¹, and eluent type = ethanol), 2.0 mL of the desorbed ethanolic solution was added to 16 mL of 10% (w/v) NaCl aqueous solution for the next HF-LPME method and the final analysis was performed by GC/MS. The developed method showed a limit of detection of 0.05 μg L⁻¹, a limit of quantification of 0.5 μg L⁻¹, a dynamic linear range of 0.5–1000.0 μg L⁻¹, preconcentration factors between 700 and 1050, and a repeatability (RSD%) of 6.9%. The suitability of the MD-µSPE/HF-LPME method was confirmed by measuring chlorpyrifos in real samples with relative recoveries in the range of 97.0–108.5%. The results showed good accuracy and precision of the developed MD-µSPE/HF-LPME method for the preconcentration and determination of trace amounts of chlorpyrifos in the aqueous samples.

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Graphene oxide-activated carbon (GO–AC) composite with different ratios of GO and AC (0.5/0.5, 0.3/0.7 and 0.1/0.9) were synthesized via direct chemical bonding of them using hydrogen peroxide as a chemical linker and used for selective removal of diclofenac sodium (DCF) and ibuprofen (IBP) from aqueous solutions. The adsorbents' surface morphology, composition, and physicochemical structure of the adsorbents were characterized by FE-SEM, FTIR, BET and XRD analysis. The synthesized composite with a ratio of GO and AC (0.1/0.9) was the most suitable among the synthesized adsorbents for both DCF and IBP adsorption. The optimal working conditions for DCF removal were at pH of 2, contact time of 40 min, initial concentration of 100 mg/L, and temperature of 293 K. For IBP removal, the optimal operating conditions were at pH of 2, contact time of 60 min, initial concentration of 20 mg/L, and temperature of 293 K. The highest adsorption capacities of 0.1/0.9 composite for DCF and IBP were 833.33 and 238.095 mg/g at 298 K, respectively. Isotherm, kinetic, and thermodynamic characteristics were assessed to analyze the adsorption process. The synthesized adsorbent displays high removal efficiency by simple recyclability with low-cost reagent and high selectivity for drug pollutants such as DCF and IBP in single and binary systems.

In order to investigate the effect of terminal donors on the structures and photophysical properties, four donor (D1)-acceptor (A)-π bridge-donor (D2) prototype fluorophores were synthesized and characterized. Single crystal analysis indicated that changing the types of terminal donors (D2) would give rise to different frontier molecular orbitals and molecular packing modes, leading to their different emission behaviors in solid states. In dilute solution, the four D–A–π-D compounds displayed different absorption and emission behaviors in dilute solution with solvatochromism properties. Assisted by the quantum chemical calculations and wave function analysis, the essence of optical properties of four compounds were explored. The results indicated that changing the types of terminal donors (D2) can affect the structures and photophysical properties of such donor (D1)-acceptor (A)-π bridge-donor (D2) prototype fluorophores, which provided guidance to design new fluorophores.

Two coordination complexes [Ni(Hpydco)₂(bpy)] (1) and [Ni(pydco)(phen)(H₂O)₂]·4.5H₂O 0.5CH₃OH (2) have been synthesized using a mixed-ligand system including pyridine-2,5-dicarboxylic acid N-oxide (H₂pydco) as an O-donor ligand and 2,2'-bipyridine (bpy) or 1,10-phenanthroline (phen) as a chelating N-donor ligand and NiCl₂.6H₂O as a source for Ni ions. The crystal structures of 1 and 2 form discrete complexes in which extensive π−π stacking interactions between aromatic rings of the N-donor ligands resulted in the formation of one dimensional (1D) chain-like structures. The chains are connected by hydrogen bonds to expand the structures into 2D-supramolecular networks. Hirshfeld surface analysis and Density Functional Theory (DFT) calculations were included to rationalize the relative strength of the π-stacking assemblies observed in both complexes.

The synthesis of 1-(4(tert-butyl)-4-methoxy-[1,1-biphenyl]-4-yl) ethenone (4TBMBE) has been realized in excellent yield by using 4-tert-butyl phenylboronic acid and 1-bromonitrobenzene as the reactants. The single crystals were obtained by solvent-loss technique and its characterization was carried out using the spectral and X-ray diffraction methods. The molecule crystallizes in the monoclinic crystal system with space group (P2₁/c). There exists one C–H…O intramolecular and an intermolecular C–H···π interaction, besides one π···π (Cg···Cg) interaction responsible for stabilizing the unit cell molecular packing. The density functional theory has been employed to optimize the structure and to carry out the HOMO/LUMO analysis, computation of reactivity parameters, molecular electrostatic potential map and Mulliken population analysis. The Hirshfeld surface analysis probes the existence of various interactions in the crystal structure. Crystal voids analysis confirmed the absence of any significant cavity within the crystal packing. The relative contribution for each contact has been analyzed using the 2D fingerprint plots and their favourability has been validated by the enrichment ratio. The 3D topology of molecular packing has been visualized using energy framework analysis and the nature of molecular interactions existing within the structure has been ascertained using NCI-RDG analysis. The molecular docking investigations have been performed to study the anti-inflammatory action of 4TBMBE against the p38 MAP kinase inhibitor.